The insect antifeedant and toxic activity of the Delphinium diterpene alkaloids 15-acetylcardiopetamine, cardiopetamine along with its amino alcohol, the beta,gamma unsaturated ketone, and the acetylated ketone derivatives were studied in Spodoptera littoralis and Leptinotarsadecemlineata. Cardiopetamine and 15-acetylcardiopetamine strongly inhibited the feeding activity of S. littoralis and L. decemlineata, respectively. Structure-activity studies with S. littoralis showed that the C13 and C15 hydroxy substituents are essential features of the active molecule, while a C13 hydroxy and/or a C15 acetate determined their effect on L.decemlineata. The C11 benzoate group enhanced the biological effect on both insect species. These alkaloids were not toxic to S. littoralis, while their toxicity on L. decemlineata was inversely correlated with their antifeedant effects, the beta,gamma unsaturated ketone derivative being the most toxic. Cardiopetamine showed little antifungal action against several species of plant pathogens and did not have any mutagenic effects on Salmonella typhimurium by means of the Ames test.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/jf970585p | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Decarboxylation of Aza-Annulation Products as a Synthetic Route to 3-Pyrrolin-2-ones and 1,2,3,4-Tetrahydropyridin-2-ones.
J Org Chem
October 2024
Department of Chemistry, School of Sciences and Humanities, Nazarbayev University, 53 Kabanbay Batyr Avenue, 010000 Astana, Kazakhstan.
Aza-annulation of enamines derived from β-ketoesters with maleic and itaconic anhydrides proceeds with excellent diastereoselectivity to provide functionalized γ- and δ-lactams. Further hydrolysis of the aza-annulation products resulted in dicarboxylic acids that underwent spontaneous decarboxylation under ambient conditions. The decarboxylation of β-γ unsaturated carboxylic acids with an electron-rich enamide C═C bond proceeds with the migration of the C═C bond and serves as a practical synthetic entry into 3-pyrrolin-2-ones and 1,2,3,4-tetrahydropyridin-2-ones.
View Article and Find Full Text PDFVisible-Light-Driven N-Heterocyclic Carbene Catalyzed γ- and ϵ-Alkylation with Alkyl Radicals.
Angew Chem Int Ed Engl
December 2019
Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
The merging of photoredox catalysis and N-heterocyclic carbene (NHC) catalysis for γ- and ϵ-alkylation of enals with alkyl radicals was developed. The alkylation reaction of γ-oxidized enals with alkyl halides worked well for the synthesis γ-multisubstituted-α,β-unsaturated esters, including those with challenging vicinal all-carbon quaternary centers. The synthesis of ϵ-multisubstituted-α,β-γ,δ-diunsaturated esters by an unprecedented NHC-catalyzed ϵ-functionalization was also established.
View Article and Find Full Text PDFSynthesis and biological evaluation of tricyclic matrinic derivatives as a class of novel anti-HCV agents.
Chem Cent J
September 2017
Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, China.
Background: 12N-benzyl matrinic acid analogues had been identified to be a novel scaffold of anti-HCV agents with a specific mechanism, and the representative compound 1 demonstrated a moderate anti-HCV activity. The intensive structure-activity relationship of this kind of compounds is explored so as to obtain anti-HCV candidates with good druglike nature.
Results: Taking compound 1 as the lead, 32 compounds (of which 27 were novel) with diverse structures on the 11-side chain, including methyl matrinate, matrinol, matrinic butane, (Z)-methyl Δ-matrinic crotonate derivatives were synthesized and evaluated for their anti-HCV activities.
Syntheses of C17-C27 fragments of 20-deoxybryostatins for assembly using Julia and metathesis reactions.
Org Biomol Chem
March 2017
The School of Chemistry, The University of Manchester, Manchester M13 9PL, UK.
Two approaches to the synthesis of compounds corresponding to the C17-C27 fragment of the 20-deoxybryostatins are described. The first approach is based on the palladium(0) catalysed coupling of tin enolates, generated in situ from enol acetates using tributyltin methoxide, with vinylic bromides. The vinylic bromides were prepared using the Sharpless asymmetric dihydroxylation to introduce the hydroxyl groups corresponding to those at C25 and C26 in the bryostatins.
View Article and Find Full Text PDFRegioselective 1,4-Conjugate Addition of Grignard Reagents to α,β-γ,δ-Dienones and α,β-γ,δ-Dienyl Thiol Esters.
J Org Chem
March 2017
Hunter Laboratory, Department of Chemistry, Clemson University, Clemson, South Carolina 29634-0973, United States.
Alkyl Grignard reagents (Et, Bu, Pr, cyclohexyl), with the exception of BuMgCl, undergo exclusive or exceptionally highly regioselective 1,4-addition reactions to α,β-γ,δ-unsaturated ketones, while aryl and heteroaryl Grignard reagents give mixed results ranging from exclusive 1,4-addition (1-naphthyl, 2-N-methylpyrrolyl) to regioselective 1,2-addition (2-furyl, 2:1). All alkyl, aryl, and heteroaryl Grignard reagents examined gave exclusive 1,4-addition reactions with α,β-γ,δ-unsaturated thiol esters, with the exception of BuMgCl, which gave an 80:20 mixture of 1,4:1,6-addition products. The high chemo- and regioselectivity observed for these reactions is attributed to a radical or radical-like pathway for the alkyl Grignard reagents and possibly a carbanion pathway for aryl Grignard reagents.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!